Devices, systems, and methods for detecting the presence of one or more analytes in a sample are described. In some variations, a test strip may be used to detect and/or analyze one or more analytes in a sample. In certain variations, a test strip configured to receive a sample for detection of an analyte therein may comprise a substrate and a coating on a portion of the substrate, the coating comprising a combination of a first analyte capture agent configured to bind to a first analyte and a second analyte capture agent configured to bind to a second analyte that is different from the first analyte.